CVE-2026-8391
Other issue in the JavaScript Engine component
CVSS Score
5.3
EPSS Score
0.3%
EPSS Percentile
22th
Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | May 12, 2026 |
| Last Updated | Jul 15, 2026 |
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Affected Versions
Mozilla / Firefox
All versions affected Mozilla / Thunderbird
All versions affected References
bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2038575 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-45/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-47/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-48/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-51/ access.redhat.com: https://access.redhat.com/security/cve/CVE-2026-8391 bugzilla.redhat.com: https://bugzilla.redhat.com/show_bug.cgi?id=2476475 security.access.redhat.com: https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8391.json access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26551 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:27715 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26539 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:21380 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:22325 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:21382 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:22643 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26629 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26270 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26606 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26536 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26630 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26268 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26491 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26269 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26493 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26174 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26492 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26521 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:21378 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:21381
Credits
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